MOSCOW — Russian prime minister Vladimir Putin on Thursday accused the US of encouraging and supporting the election protests that have taken place in Moscow over the past three days.

Putin lashed out at US secretary of state Hillary Clinton, who he said had criticized Sunday’s elections before even reading the reports of international monitors, AFP reported.

He accused Clinton of deliberately sending a signal to the opposition to protest by questioning the fairness of the weekend’s parliamentary polls.

Putin said the US was paying Russian groups to find fault with the elections and that its criticism had “given a signal” to his opponents.

About 1,000 protesters were arrested in Moscow over the past three days as people demonstrated against alleged fraud in Sunday’s parliamentary polls.

Russian president Dmitry Medvedev pledged Thursday to investigate all allegations of fraud, the Ria Novosti news agency reported. Speaking during a visit to Prague, he added that the videos uploaded to the internet of alleged electoral violations were not proof of fraud and called for calm.

Clinton complained earlier this week that the Russian polls were neither free nor fair, and following talks with Russian foreign minister Sergei Lavrov in Brussels on Thursday, she did not soften her line.

“We expressed concerns that we thought were well-founded about the conduct of the elections,” she told reporters in Brussels.

In a further US-Russia development, Clinton said that US-backed plans for a European missile shield should be no cause for countermeasures, after Russia threatened to deploy missiles near Europe.

“We will continue to press forward on missile defense,” Clinton said. “It is certainly not a cause for military countermeasures,” she said.

Clinton added, “This is not directed at Russia. It is not about Russia. It is frankly about Iran and other state or non-state actors who are seeking to develop threatening missile technology.”

Medvedev announced last month that Russia was ready to deploy intermediate range missiles along the border of Poland and Lithuania, in response to the missile plans.